Re: Iterator-Template problem

From:

ricecake@gehennom.invalid (Marcus Kwok)

Newsgroups:

comp.lang.c++

Date:

Sun, 18 Mar 2007 22:08:47 +0000 (UTC)

Message-ID:

<etkd9f$hud$1@news-int2.gatech.edu>

nguyen.h.khanh@gmail.com wrote:

Hi,

I have this code

#include <vector>
#include <string>
#include <iostream>

using namespace std;

template <class T> void print_list(const vector<T>& v){
typedef typename vector<T>::iterator i;

Here, you create a typedef for vector::iterator, and call this type 'i'.

for (i = v.begin();i != v.end(); ++i)

Here, you are trying to assign a value to a type, similar to if you did:

   for (int = 0; int != v.size(); ++int)

You need to declare a variable of that type before you can use it.
For clarity, I would call the typedef 'it':

   typedef typename vector<T>::iterator It;
   for (It i = v.begin(); i != v.end(); ++i)

               cout << (*i) << " ";
       cout << endl;
}

int main(){
       vector<int> l(5,1);
       print_list(l);
       return 0;
}

when i tried to compile, it gave

ch3list.cpp: In function `void print_list(const std::vector<T,
std::allocator<_C
harT> >&)':
ch3list.cpp:11: error: expected primary-expression before '=' token
ch3list.cpp:11: error: expected primary-expression before '!=' token
ch3list.cpp:11: error: expected primary-expression before ')' token
ch3list.cpp:12: error: expected primary-expression before ')' token

what did I do wrong here?

See above.

--
Marcus Kwok
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